


Lifting all the Spirits

by rehliamonster



Series: Prostitute Sans Series [5]
Category: Undertale (Video Game)
Genre: Crying, Dom/sub Undertones, Ecto-Genitalia (Undertale), Ecto-Tentacles (Undertale), Ectobiology, Fluff and Smut, Gentle Sex, Kink Negotiation, Loud Sex, Masturbation, Naked Cuddling, Non-Human Genitalia, Oneshot, Other, Plot What Plot/Porn Without Plot, Possession, Praise Kink, Prostitution, Tentacle Sex, Touch-Starved, Unusual Genitalia, Voluntary Prostitution, mutual praise
Language: English
Status: Completed
Published: 2018-07-13
Updated: 2018-07-13
Packaged: 2019-06-10 01:27:18
Rating: Explicit
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 4,511
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/15280554
Author URL: https://archiveofourown.org/users/rehliamonster/pseuds/rehliamonster
Summary: Sans is calm and cheerful, which is just what Napstablook needs for tonight.He feels proud of his job.





	Lifting all the Spirits

**Author's Note:**

> The next part of the series~ Thank you to Megalotrash for the support of this part :D I hope you enjoy it^^
> 
> If you wanna influence what I write next, check out [my Tumblr](https://rehliamonster.tumblr.com/)!

Here we go, Sans thought as he pressed the doorbell. 

He know exactly who lived in this house, just like last time. But unlike last time, he wasn't sure if he'd be able to coast by on audacious bullshit humour. 

Which was a bit of a problem, considering that audacious bullshit humour tended to be his default.

He looked around as he waited, took in the rounded shape of the house, that of its twin next to it, the snail farm in the distance. Waterfall was quiet. So was the inside of the house. 

Oh man. 

He rang the doorbell again. 

Finally, there was a soft click as the door swung open, revealing the translucent form of a ghost. 

“i'm sorry… for taking so long… i thought someone had come to the wrong door…” 

Napstablook already looked as if they were close to crying, folding in on themselves with insecurity. Clearly, a gentle approach was in order. He knew from the referral that they had only asked for a very special set of services - services only he could provide. They'd take anyone if necessary. But they had also hoped for someone who wouldn't make them nervous. Sans would just have to try his best. 

“no worries, it happens,” he said, trying to project a relaxed and soothing manner. “can i come in?”

“oh… yes… of course…”

Napstablook moved aside, closing the door behind Sans once he walked in. 

They had a small house, and it looked looked a little run down, with little in the way of comfort. There was a fridge, a TV and a computer table, some records lying around. A cobweb with a spider bakesale flyer in a corner. No bed, no chairs. Sans didn't mind much given that his own room hardly looked better but wasn't sure where he should put himself. For now he just stayed in the centre of the room, hands in his hoodie pockets, and tried to look casual. 

Even when he turned to face them, Napstablook remained silent, looking at the ground. They seemed insecure and not sure what to say. They wouldn't be the first monster to be overwhelmed with the reality of this situation, so Sans decided to take the initiative. 

“so. since you're a new client, let's talk about our rules, likes and dislikes first.” He phrased it in a tone that could be interpreted as question or as a statement, depending. Would they feel intimidated if he led the conversation? Or would they feel anxious if they had to start? 

Considering that he had more experience, he felt it made more sense for him to start. 

“you already know about keeping this stuff secret, of course.” 

It was a statement, but also a reassurance for both of them. Prostitution in the Underground was an open secret, but still a secret. Pretty much everyone knew it was happening, but meetings only happened based on referrals or direct requests. You had to know who was offering and buying what, or know someone who could refer you. Speaking openly about who offered a service or who bought it? You'd be shunned. The monster population had grown but was still relatively small. Most monsters knew most other monsters and privacy was at a premium. Anyone who compromised this valuable privacy, especially for something as intimate as purchased companionship and sex, would draw the wrath of the whole population on them. 

“yes… i wouldn't talk about it.” The last statement sounded a lot stronger and more confident than their usual speech. They'd definitely take this seriously. Which made sense; Sans couldn't imagine that someone as introverted as them would be comfortable outing themselves or someone else this way. 

“cool. just checking for protocol, you know?” They nodded, and he went on. “in addition to that, i have three more rules i wanna stick to. one of my rules is that my brother, papyrus, can't ever find out. not even through a referral or anything else. it’s a sibling thing.”

He had recently started to add that last part so people wouldn't assume that Papyrus was too innocent to know. He wasn't. Sans simply didn't want to have the whole conversation about how he liked being paid for sex better than relationships or intimacy with his rather romantically-minded bro. Too much effort. 

“okay…..” 

“second rule is, no pain or harm. don't care if you wanna dom me or whatever, but nothing happens that could hurt me.” Sans was reasonably sure Napstablook wouldn't want that anyway, but there was always a chance he might be wrong. Some monsters had very surprising kinks, in his experience. 

“i don't like pain either………..” they assured him. 

“nice. seems like this will be a good referral then,” Sans grinned. Napstablook seemed to be both happy and embarrassed by this assertion, so Sans moved on. “final rule….”

He paused. His usual way of stating this might be a bit tough on someone like them, so he'd have to rephrase it. 

“i like to take it easy,” was what he finally settled on. “i prefer not exerting myself. i can be on top or bottom or whichever position you prefer, but i don't wanna strain myself too much.”

The implication was that they'd have to do the work, but Sans felt that he did a good job putting it in a nicer way. 

It seemed to have worked because Napstablook looked very relieved. 

“and that's it from my side. anything you wanna add? anything i should consider?” he prompted. 

“oh… uhm… no… i like… when it's gentle and calm… with praise and kind words… “ they admitted, avoiding his gaze. 

“neat.” 

He carefully guided them through the next part of the conversation, having them tell him what exactly they wanted so he could tell them his price. That was even more difficult than the part before, as the ghost had real trouble articulating their desires out loud. Good thing they had the whole night, really, so it wasn’t too much of a loss that they spent some time on this. It all worked out in the end though. 

“alright, give me a sec,” Sans told them once he had pocketed his pay. He removed his hoodie, shirt, and shorts so he stood naked before them. 

He closed his eyes and focused. 

Since he had only done this recently, he found it easy to send his magic over his body to form ectoplasmic flesh. Unlike last time, there were no indicators of gender. It was just the shape that came naturally to him, chubby flesh covering his bones, but without any extra features. Another difference to last time he did this was the scope; he now allowed the ectoplasm to not only cover his torso and upper limbs, but had it spread over the entirety of his body, even over his skull. 

When he was done, his sockets were the only thing not covered, so his field of vision was still clear. The whole rest of him was glowing faintly blue with his magic. 

“there we go,” he said and opened his arms in a welcoming gesture. 

Napstablook hesitated for a moment, but then they quickly hovered closer and pressed themselves against him. When their form touched his ectoplasm, they sighed deeply. Sans felt a soft, tingling warmth from where they touched. It was pleasant, different from touching a monster without ectoplasm with his conjured flesh. 

He wrapped his arms around Napstablook and hugged them close, running a hand over their back and coming to a rest on their middle. The other hand petted their head, stroking over the curve of it. 

They remained like this until Sans felt them shudder, a forcefully silenced sob barely audible in the quiet if the room. He could feel their tears on his conjured flesh too, stinging but not hurting him due to the lack of intent to harm. 

Aw man. 

Napstablook hadn't named any reasons for why they wanted him to conjure all this ectoflesh, but it wasn't hard to guess. Their cousins had all left and become corporeal from what Undyne said, and they didn't want to be corporeal themselves. Additionally, there weren't a lot of other ghost monsters in the Underground. Even if there were, Napstablook would probably find it difficult to approach them for this. 

Corporeal monsters couldn't touch ghosts or vice versa. 

Oh, they could interact, sure. Ghosts could project small shields with their magic to stop monsters from running into them, and they could use that magic to interact either corporeal monsters and everyday items too. But it was only magic and it didn't replace true touch on their actual bodies. The shield was in contact, not the ghost. Like the opposite of his ectoplasm - their magic could use magic to interact with the world while their bodies remained untouchable, his magic could interact with ghostly matter while he still remained corporeal.

Which meant Napstablook had been without someone to touch for however long it had been since their cousins left. 

No hugs, no pats on the back, no handshakes, nothing. Only passing through everything and everyone, surrounded by people and yet separated and alone. 

He felt awfully sorry for them. That was a terrible way to live. No wonder they had overcome their own shyness just to get some touches from him. As one of the few monsters capable of conjuring ectoplasm, Sans was in the position of being able to interact with corporeal and ghost monsters alike if he so wanted. Among the prostitutes, that made him unique. He was the only one capable of providing this service. It had perks to be unique in this aspect, although most monsters used his abilities for more mundane things, relatively, like having him imitate specific body types or conjuring several sets of genitalia at once. 

This was the first case where he truly felt that his abilities were more than just a neat gimmick. 

Being able to fill this hole in Napstablook’s life, being able to help them even if it was a paid service - it made him strangely happy and proud. He always felt as though he was helping monsters with his services and he always felt happy to do so, but it had never felt so essential as this. 

“i'm… sorry…” they mumbled into his chest, a sniff interrupting their sentence. 

“it’s okay,” he assured them. “i get it.”

They relaxed more against him, their sniffles slowly subsiding as he kept soothing and petting them for a long while. He began trailing his fingers over their back, drawing nonsensical lines there. Their body positively melted against him, molding itself to fit perfectly against his conjured flesh. It was an interesting sensation. Their entire body seemed very flexible, almost malleable. It was very soft in any case, like shaped silicone. 

Should he go further already? 

He tried angling his head to the side, using the ectoplasm over is mouth to nuzzle and kiss their head. Heat spread from where he touched them, tingling through his magic until it reached his bone. 

It must have been okay, because Napstablook tilted their face up to meet him, shyly pressing their mouth against his. In a surprisingly bold display, they even licked across his temporary lips, tangling their tongue with his when he opened his mouth. Their breath was cooler than his, the ghostly chill of their existence coming through, but it wasn't unpleasant. It mixed with the heat that was created where his ectoplasm and their ghostly flesh met, creating an exciting contrast. He allowed his sockets to close and just enjoyed the sensations. 

His tongue curled around theirs, interrupting their exploration of his mouth by sucking on it, and he heard a sigh from then that wasn't sad or dejected. It was pleased. 

There we go, he thought, suppressing a grin. 

Trailing the tip of his tongue over the underside of theirs, he teased a shudder out of them that was accompanied by the hitch of their breath. 

He could feel his ectoplasm and their ghostly matter overlapping and intermingling the longer the two of them stayed pressed together. Not surprising, since his ectoplasm wasn't quite the same as their incorporeal body. It occupied the border of corporeal and incorporeal, and could be interacted with by corporeal and incorporeal monsters both. He thought it was a fascinating sensation and based on their low sigh, they liked it too. 

When their mouths parted and his sockets opened again, he was in for yet another new sensation. 

“what…?”

The two of them were standing among stars, deepest black scattered with bright flecks of light in yellow, white and blue. Some larger, some smaller, all twinkling beautifully. A cosmic hum could be heard, rising and falling, and peace spread in his soul. He could still feel the wooden floor under his feet, but the illusion was incredibly convincing. 

“oh…sorry… this sometimes happens if I don't move much for a while…” Napstablook apologised. “we can move… and stop this…if you want…”

“no, no, this is fine!” Sans hurried to say, still taking in the beautiful scenery with wide sockets. “this looks really cool. and realistic. i love the stars…”

When he managed to pry his gaze away from the vista, he found Napstablook smiling widely. A gentle flush covered their whole face. He hadn't ever seen them this happy before. 

“i’m… happy you like it…” they told him. 

“unexpected bonus,” he told them with a wink. They blushed harder at the implication. Cute. He bent over to kiss them again. “thanks.”

They accepted his kiss eagerly. Where his body and theirs connected, he could feel the overlap of their essences increase. The heated tingle between them grew stronger and stronger. 

It was time, he could feel it. Time for the main event.

The ectoflesh on his ribcage and belly wavered just as Napstablook’s front did the same. They both didn't move, but between them, a series of rapid shifts were happening. 

A row of thin, short filaments grew in two parallel lines from his chest down to his belly, mirroring the development on Napstablook’s body. In the middle between those lines, an opening grew, layered like the fleshy petals of a flower, ringed by suckers and longer pseudopods. At the bottom of the pulsing opening sat a single, thick tentacle.

Immediately after formation, his and Napstablook’s newly formed genitals began to seek each other out and mingle. The tentacles at the bottom wormed their ways up to the openings, touching each other and overlapping on their ways there. He heard Napstablook moan and released a grunt of his own when a spike of lust raced through his body. The tentacles were extremely sensitive. The stimulation of having them touch directly was almost too much for him right now. 

It was a relief when the tentacles found the openings and inserted themselves fully. The fleshy holes seemed to sucked the tentacles in, rippling with inward motions. Sans felt better now that his tentacle was fully sheathed inside Napstablook, cradled and safe from overstimulation. Napstablook’s ghostly flesh was tight around the tentacle, but in a good way. It fluttered against the organ only slightly, massaging it while leaving the sensitive head be. At the tip of his tentacle, there was a receptor through which he could feel a soft pulse of magic and more. 

He could, almost, feel Napstablook’s soul. 

He knew that Napstablook could feel his soul in the same way. They would not touch their souls, that was a hard limit they had both set. But it was extremely pleasant to feel this hint of concentrated soul magic through his tentacle. This was a set of genitals he was using for the first time and he really liked it so far. 

The rest of the setup joined the fun immediately after. The pseudopods began winding around each other while the suckers began working to connect. The rows of filaments rippled and caught, and the end result was that the two of them were firmly connected, inserted in each other, sucked close and parts of them overlapping. 

Sans wouldn't have been able to tell where he ended and where Napstablook began even if he tried. 

The ghost was breathing faster now, little pants and hiccups sighed into his shoulder where they were hiding their face. 

Sans was calmer, but only because of experience. He'd had a lot of sex ever since he started this line of work for extra cash. Even so, he found it increasingly difficult to remain quiet and still. 

His new genitalia reacted to his desires and began moving. The pseudopods wound around Napstablook’s began pulsing, sending ripples of heat through him. His tentacle slowly started to undulate inside of the ghost. It wasn't anything he thought about. He was moving on autopilot, following his instincts, trusting his body and his experience with sex to lead him towards what felt good. 

“oh… yes…” Napstablook moaned.

That had been… surprisingly loud. It completely drowned out Sans’ own groan. He focused on keeping the movement up, panting against the ghost. His hips were twitching, he couldn't help it. He was too used to that doing something, even though right now it was a useless motion. 

“mh… ah…”

“more?” he asked Napstablook in a low voice, the kind that he knew rumbled through the other's body. Most monsters enjoyed hearing him like that. Judging from Napstablook’s shudder, they were no exception. 

“yes… please… i need more… it feels so good...”

Holy shit, they were vocal. He almost wanted to tease them for it but that wasn't part of the plan. Praise only.

“you’re sexy like this,” he told them instead, murmured it against their head. They were still hiding their face in his shoulder, so he couldn't see the blush fully. There was only a hint of colour visible at the sides. 

“i… i’m not… oh… ah…” 

“you are,” Sans insisted, squeezing their body. “you have a nice voice. sounds good when you tell me what you want.” 

“mmmh… i… ah…” 

Their voice grew increasingly needy. Their tentacle inside of Sans finally began moving too, wrenching a surprised moan out of him even though their motions were more hesitant and inexperienced. 

“haaangh. shit…”

He had been penetrated before, and deeply, but he hadn't ever had something penetrate him so close to his soul. He could feel the magic of the appendage so close to the most intimate and important part of him. So close to everything that he was. It was a rush of intensity that was completely unfamiliar to him. Almost dangerous, and yet not, because he could also feel the _intent_ of the magic radiate outwards from the tip of the tentacle, and he understood on a soul deep level that Napstablook would not cross that line, that he was _safe_. He imagined they must feel the same from him and focused on that thought, wanting them to feel it now.

“you feel so good… “ Napstablook moaned, shuddering against him. “so warm… soft… safe… i need you… i need more… please…”

“what do you need,” he mumbled, himself panting with the desire for more of this. “tell me.”

Napstablook merely moaned louder against him, their voice almost pitching into a whine. 

“i want to make you feel good,” he told them, intent to fuel their lust with the praise they had specifically requested. He submitted to them, in a way. It was abundantly clear that they got off to hearing this, even if they could barely admit it, even if they might not even be fully aware that their praise kink was sliding into a thing for seeing him surrender to them. “please, let me do this for you. i want to. please let me…”

“ah!!!” 

Napstablook cried out against him and he felt a rush of magic spread from his tentacle, quickly being absorbed by his ectoflesh and his soul. Despite the suddenness of Napstablook’s climax, Sans felt that the flow of energy was relatively gentle and invigorating, not jolting him as much as he would have expected. 

He didn’t come himself yet so instead he got to watch every pleased shiver and twitch of the ghost. It lasted for a while, just like the energy they were pumping inside of him. 

“you’re so pent up…” he murmured to them. “this is good. let it all out. i like being filled by you.” 

A warbled whine made its way out of their mouth, accompanying a final shudder. Then they panted against him, trying to catch their breath in the aftermath of their intense orgasm. 

“ah… you haven’t… “ they fretted as they pulled back a little. Not enough that their genitals would separate, but enough that they could look at him with a flushed and embarrassed expression. 

“it’s fine,” Sans assured them. “we got all night.”

“let me… try this…” they begged him, pressing closer again. Their ghostly mattered overlapped with his ectoflesh again, but this time there was no stop to it. They slid against him and into him, and Sans had the strangest feeling. 

He felt filled, but not in the way that a cock in his pussy would fill him or a good burst of cum would fill him with magic. It was as though a fresh breeze of air from Snowdin and a warm draft from Hotland combined and blew inside his bones, spreading through the leylines where his magic flowed until his innermost core was just as filled as his extremities. There was a presence inside of him. 

_mmmh… your body is nice… so sturdy and soft at the same time…_

The voice came from inside his head, not speaking out loud and yet as clear as it could be. 

_whoa_ , he thought back. _this is a trip._

_is it… too much… ?_

_nah. just new. ‘s fine, go on._

He felt a nudge and looked down at himself. A motion he had initiated, but at the prompt of someone else. His ectoplasmic skin and genitals were still fully summoned, the latter swirling and undulating in the air now that they didn’t have a matching set to work with anymore. At another nudge he raised one of his hands to the tentacle, stroking the underside from the base to the oversensitive tip. 

“ah… fuck…” 

_now down… and here…_

There were both verbal and nonverbal instructions. Sans followed them all without thinking, allowing the ghost inside of him to partially take over. He was still in control, could have pushed Napstablook aside at any time, but he allowed them enough control to direct his arms and fingers directly. 

They were moving together easily. 

His phalanges trailed back down on the tentacle, moving from the base upwards towards the hole. He caressed the pseudopods surrounding the opening, pressed his carpals against one of the suckers while the pseudopods wound themselves around his distal phalanges and squeezed. 

“ngh…” he sighed. This felt really good. Napstablook might be inexperienced when it came to using their genitals on others but they clearly knew their way around masturbating with them. 

Slowly his fingers moved towards the centre, towards the opening. He toyed with the petal-like flesh there, stroking the flat of it, taking one here to stroke the underside and the top of it at once, taking one there to pinch it ever so gently. 

“oh stars…” he groaned. “that’s… ha…”

While his fingers continued to play with the rim of his opening, his other hand came up to tease the base of his tentacle again. 

_be gentle here..._ Napstablook whispered from inside of him. 

Sans couldn't a respond with anything but a moan. He was too overcome by the unfamiliar feelings washing over him, the new pleasure that built from his conjured genitals to spread through his body. His sockets were half open, threatening to flutter shut and only kept open by his desire to keep watching the beautiful expanse of stars around him. The low droning hum of the illusion put him into an almost meditative state as his fingers inched deeper into his opening and out, teasing the rim while his other hand squeezed the lower half of the tentacle. Magic began to leak out of the tip in small pearls. He felt as though it was getting harder to breathe. 

“oohffuck… please i… you're so good at this. please let me… let…” he babbled, having no consciousness for what came out of his mouth anymore. 

_here… put it in..._ Napstablook told him. 

The hand on his tentacle was guided upwards, until he had inserted his tentacle into his own pulsing hole, his hands still toying with the underside of the appendage and the outer rim of the hole while the tentacle pumped and pulsed inside of him. 

“shit… ah… this is so…”

It was a dizzying double sensation of penetrating and being penetrated, not as strong as when he had fucked Napstablook directly but still heightened because it was so focused on himself. 

Despite that, he could hear Napstablook moan in the back of his mind too, clearly enjoying this just as much. Sans wondered absentmindedly how much of his physical sensations they could feel while possessing him. 

All thoughts and curiosity in that direction evaporated immediately when his movements sped up. His distal phalanges touched the base of the tentacle only with the very tips to create a tickling, scratching sensation while the tentacle itself sped up inside his hole. 

“aaah… yes… more…”

_yes..._

“nghh!!”

Sans tensed, his tentacle gushing magic inside of him while the walls of his opening rhythmically massaged the organ. His orgasm was a soft one, washing over him like a refreshing breeze, a wave of please that spread a tingle of sensation through his extremities and left him feeling light and happy. He grinned at the stars that were still sparkling around of him while he relished the aftershocks, his expression lazy and satisfied. Only when the last remnants of his orgasm abated and he dispelled his genitals did Napstablook emerge from inside of him, shattering the illusion around him. 

The slightly shabby interior of the house replaced the cosmic beauty of the stars. 

The ghost looked at him with a small smile. They seemed less insecure than the did initially, calmer and not as sad. 

Good. 

Sans pulled them close again so they could cuddle more, sitting down on his discarded clothes on the floor. He was a bit tired from having done all of that while standing up. Neither of them talked, as there was no need. They had both experienced those last moments together and knew it had been pleasant for both of them.

And they both knew it wasn't the end yet. 

Just as Napstablook had requested, he kept hugging and petting them, caressing their body. They had wanted as much touch and affection as they could possibly get during this night in between their sexual play. 

And while Sans definitely looked forwards to the next round with those interesting genitals, he enjoyed these soft caresses just as much.


End file.
